Slurry reactor hydrocracking oil residue extraction method

Abstract

The invention provides a slurry reactor hydrocracking oil residue solid removal method which comprises the following steps: slurry reactor hydrocracking oil residues are subjected to N-stage extraction, N is an integer greater than 2 and can be specifically 2, 3, 4, 5 and 6, a solid-phase material obtained by separating a material subjected to previous-stage extraction is subjected to next-stage extraction, and a solid-phase material obtained by separating the material subjected to previous-stage extraction is subjected to next-stage extraction. The Nth-stage extracted material is subjected to solid-liquid separation and then can be subjected to subsequent treatment respectively. When the method is used for treating the oil residue of the slurry reactor, an adsorbent does not need to be added, the mass ratio of the solvent to the oil residue is small, the extracted oil content is high, the metal content in the extracted oil is low, and the related problems existing in the process of simply treating the hydrocracking oil residue of the slurry reactor through extraction in the prior art are solved.

Description

Technical Field

[0001] The invention belongs to the technical field of efficient conversion of oily waste residues, and relates to a method for extracting slurry-bed hydrocracking discarded oil residues. Background Art

[0002] With the shrinking supply of light crude oil, the conversion and refining of inferior feedstocks, such as heavy crude oil and vacuum residue (VR), has attracted widespread attention, and research on related catalysts has become a hot topic. Compared to light crude oil, inferior feedstocks have lower API gravity (≤21°) and are inexpensive, offering promising prospects for refining and conversion. However, their high levels of sulfur, nitrogen, and metallic impurities, along with a significant proportion of high-boiling-point heavy hydrocarbons, present challenges in upgrading and converting these inferior feedstocks (viscosity reduction, boiling point reduction, desulfurization, demetallization, and increasing the H / C ratio). For example, VR contains 10% to 30% polycyclic aromatic hydrocarbons and heteroatom asphaltenes, with a boiling point exceeding 813K, making it highly susceptible to coking during processing.

[0003] Hydrocracking (HCK) is an important method for converting low-quality feedstocks into low-boiling-point distillates. Slurry-bed hydrocracking utilizes a homogeneous catalyst that mixes well with the feedstock, resulting in strong coke suppression and a conversion rate exceeding 95%. This technology offers significant advantages in adaptability and selectivity for low-quality feedstocks. Despite this, slurry-bed hydrocracking remains unable to fully utilize low-quality feedstocks. This is primarily due to the need to remove some of the coked residue to prevent the impact of coking on the hydrocracking process during the recycling process. This removed residue is characterized by low saturates, high colloidal asphaltene content, high residual carbon content, and metal enrichment. This amount typically accounts for over 3-10 wt% of the plant's processing capacity. For a 100-ton / year slurry-bed plant, for example, a conservative estimate suggests that over 30,000 tons of this residue is required annually. Currently, the main methods for disposing of this residue are gasification to produce hydrogen followed by incineration to recover a small amount of metals or as fuel for steelmaking. This generally has low economic value and results in significant carbon emissions. Therefore, the efficient and comprehensive utilization of the removed residue from the slurry bed has enormous economic potential.

[0004] A limited number of reports exist on the treatment and utilization of discarded oil residue. CN 113736509 A reports a method for treating residual oil from slurry-bed hydrogenation of residual oil. This method mixes the residual oil with solvent oil and a porous material to remove metals from the residual oil. The solvent oil is then separated and recycled, and the residual oil can be further processed as a coking or hydrogenation feedstock. CN 111394122 A discloses a process for treating hydrogenation tailings, its uses, and design methods. This method utilizes the differences in solubility of heavy distillate components in a solvent to extract the light components from the heavy components, separating them. The light components are then separated from the solvent through distillation. The mass ratio of the extractant used as the tailings solvent to the tailings is 15-25:1. Existing methods for treating hydrogenation tailings through solvent extraction suffer from problems such as high solvent usage, low extraction efficiency, and high metal ion content in the extracted liquid phase. Summary of the Invention

[0005] To address the shortcomings of the prior art, the present invention provides a method for extracting slurry bed hydrocracking oil residue. Through in-depth research, the inventors discovered that the composition of slurry bed hydrocracking oil residue is relatively complex, and controlling the conditions during the extraction process significantly affects the extraction effect. The present method eliminates the need for external adsorbents when treating slurry bed oil residue, reduces the solvent-to-residue mass ratio, and produces a high extracted oil content with low metal content. This method addresses the problems associated with the prior art of simply extracting slurry bed hydrocracking oil residue.

[0006] The present invention provides a method for desolidifying oil residue from slurry bed hydrocracking. The method comprises the following steps: subjecting the slurry bed hydrocracking oil residue to N-stage extraction, where N is an integer greater than 2, and specifically N can be 2, 3, 4, 5, or 6; subjecting the solid phase obtained after separation of the material from the previous stage of extraction to the next stage of extraction; and subjecting the material from the N-stage extraction to solid-liquid separation, respectively, for subsequent treatment.

[0007] In the method of the present invention, the feed temperatures of the extracted materials in two adjacent stages can be the same or different. Preferably, different feed temperatures are used. More preferably, the feed temperatures show a decreasing trend. The difference between the feed temperatures of two adjacent stages is 25-80°C, preferably 30-70°C.

[0008] In the method of the present invention, the feed temperatures of the adjacent two-stage extraction solvents tend to increase, generally with a difference of 20 to 60°C, preferably 25 to 50°C.

[0009] In the method of the present invention, the pumping temperature of the first-stage extraction slurry bed hydrocracking oil residue is 180°C to 300°C, preferably 200°C to 280°C, and the pumping temperature of the extraction solvent oil is 15°C to 70°C, preferably 20°C to 50°C.

[0010] In the method of the present invention, the mass ratio of the extracted material to the extraction solvent in any two adjacent stages can be the same or different. Preferably, the mass ratio of the extracted material to the extraction solvent in the two adjacent stages shows a decreasing trend.

[0011] In the method of the present invention, the mass ratio of the first-stage extracted slurry bed hydrocracking oil residue to the extraction solvent is 1:2-1:6, preferably 1:3-1:5; the mass ratio of the extracted materials to the extraction solvent in adjacent two stages is reduced by 10%-90%, preferably 20%-80%.

[0012] In the method of the present invention, the slurry bed hydrocracking oil residue has the following properties: residual carbon ≥ 36wt%, ash ≥ 0.6wt%, dynamic viscosity (135°C) ≥ 50mPa·s, dynamic viscosity (250°C) ≥ 10mPa·s, distillate volume at 350°C ≤ 2wt%, distillate volume at 540°C ≤ 55wt%, and metal content of 3500-4500mg·kg-1 , preferably 3750~4250mg·kg -1 .

[0013] In the method of the present invention, the extraction solvent can be aromatic hydrocarbons, diesel, or wax oil. When the solvent is an aromatic hydrocarbon, it can specifically be at least one of benzene, biphenyl, naphthalene, anthracene, toluene, p-xylene, o-xylene, m-xylene, diphenylmethane, triphenylmethane, p-diethylbenzene, m-diethylbenzene, n-propylbenzene, isopropylbenzene, butylbenzene, isobutylbenzene, pentylbenzene, dodecylbenzene, and hexadecylbenzene. When the solvent is diesel, it can specifically be light diesel of various grades, or it can be crude oil obtained by crude oil fractionation, hydrocracking, or catalytic cracking. When the diesel is crude oil, it should have the following properties: residual carbon ≤ 0.1wt%, ash ≤ 0.05wt%, dynamic viscosity (135°C) ≤ 8mPa·s, distillate at 350°C ≥ 85wt%, and distillate at 540°C ≥ 98wt%. When the solvent oil is wax oil, it can be atmospheric wax oil, coker wax oil, etc. The atmospheric wax oil and coker wax oil should have the following properties: residual carbon ≤ 1.0wt%, ash ≤ 0.08wt%, dynamic viscosity (135°C) ≤ 8mPa·s, and distillate volume at 540°C ≥ 98wt%.

[0014] In the method of the present invention, the extraction solvents at any stage may be the same or different, preferably different. It is further preferred that the extraction solvent at the first stage is diesel and / or wax oil. When the solvent is diesel, it may specifically be light diesel of various grades, or it may be crude oil obtained by crude oil fractionation, hydrocracking, or catalytic cracking. When the diesel is crude oil, it should have the following properties: residual carbon ≤ 0.1wt%, ash ≤ 0.05wt%, dynamic viscosity (135°C) ≤ 8mPa·s, distillate at 350°C ≥ 85wt%, and distillate at 540°C ≥ 98wt%. When the solvent oil is wax oil, it may be atmospheric wax oil, coker wax oil, etc., and the atmospheric wax oil and coker wax oil should have the following properties: residual carbon ≤ 1.0wt%, ash ≤ 0.08wt%, dynamic viscosity (135°C) ≤ 8mPa·s, and distillate at 540°C ≥ 98wt%.

[0015] In the method of the present invention, the slurry bed hydrocracking oil residue undergoes two-stage extraction, the first-stage extraction solvent is diesel and / or wax oil, and the second-stage extraction solvent is aromatic hydrocarbons. When the solvent is an aromatic hydrocarbon, it can specifically be at least one of benzene, biphenyl, naphthalene, anthracene, toluene, p-xylene, o-xylene, m-xylene, diphenylmethane, triphenylmethane, ethylbenzene, p-diethylbenzene, m-diethylbenzene, n-propylbenzene, isopropylbenzene, butylbenzene, isobutylbenzene, pentylbenzene, dodecylbenzene, and hexadecylbenzene. When the solvent is diesel, it can specifically be light diesel of various grades, or it can be crude oil obtained by crude oil fractionation, hydrocracking, or catalytic cracking. When the diesel is crude oil, it should have the following properties: residual carbon ≤ 0.1wt%, ash ≤ 0.05wt%, dynamic viscosity (135°C) ≤ 8mPa·s, distillate at 350°C ≥ 85wt%, and distillate at 540°C ≥ 98wt%. When the solvent oil is wax oil, it can be atmospheric wax oil, coker wax oil, etc. The atmospheric wax oil and coker wax oil should have the following properties: residual carbon ≤ 1.0wt%, ash ≤ 0.08wt%, dynamic viscosity (135°C) ≤ 8mPa·s, and distillate volume at 540°C ≥ 98wt%.

[0016] In the method of the present invention, the number of cyclic extractions in any one stage of extraction is 1 to 6 times, preferably 2 to 4 times; and the time for each cyclic extraction is 10 to 60 minutes, preferably 20 to 40 minutes.

[0017] In the method of the present invention, the solid phase material can be further processed, or directly coked or compounded with slurry bed hydrocracking oil residue for gasification and hydrogen production; the liquid phase material is used for subsequent processing and refining.

[0018] Compared with the prior art, the slurry bed hydrocracking oil residue extraction method of the present invention has the following advantages:

[0019] (1) The method of the present invention adopts a multi-stage extraction process, which improves the utilization rate of the extraction solvent, reduces the amount of extraction solvent used, and significantly reduces the processing volume of the mixed extracted oil obtained after separation;

[0020] (2) The method of the present invention has high extraction efficiency, large amount of extracted oil and low metal content in the extracted oil. DETAILED DESCRIPTION

[0021] The slurry bed hydrocracking oil residue extraction method of the present invention is further described below by comparative examples and specific examples, but does not constitute a limitation of the present invention. The separation described in the context of the present invention is carried out by static treatment, and after liquid-solid separation, solid phase material and liquid phase material are obtained respectively.

[0022] The extracted oil yield w described in the embodiments of the present invention and the comparative examples is calculated according to formula (1):

[0023]

[0024] Where:

[0025] w—extracted oil yield, %;

[0026] m1—mass of oil residue raw material, kg;

[0027] m2—mass of dry solid phase, kg;

[0028] The metal ion content n of the extracted oil in the embodiments and comparative examples of the present invention is calculated according to formula (2):

[0029]

[0030] Where:

[0031] n—metal ion content of extracted oil, mg / kg;

[0032] n1—metal ion content of liquid phase material after desolidification, mg / kg;

[0033] n2—metal ion content of the solvent used for desolidification, mg / kg;

[0034] m1—mass of oil residue raw material, kg;

[0035] m2—mass of dry solid phase, kg;

[0036] m3—total weight of liquid phase material after desolidification, kg;

[0037] m4—total weight of solvent used for desolidification, kg;

[0038] The raw materials described in the Examples and Comparative Examples of the present invention are all oil residues discarded from a slurry bed hydrocracking unit of a certain company. The main properties of the oil residues are shown in Table 1. It should be noted that the description of the slurry bed hydrocracking oil residues (hereinafter referred to as oil residues) in Table 1 is only for the purpose of describing the basic properties of slurry bed oil residues and facilitating the illustration of the desolidification effects and differences of the oil residues in the Examples and Comparative Examples, and does not constitute a limitation on the raw materials selected for the present invention.

[0039] Table 1 Physical properties and control indicators of oil residue raw materials

[0040]

[0041] Example 1 (Examples 1 to 6 are the second level) The effect is in the middle

[0042] The oil residue was desolidified using diesel produced by the catalytic cracking unit (catalytic diesel) as solvent. The basic physical properties of the catalytic diesel were: residual carbon 0.062 wt%, ash 0.017 wt%, dynamic viscosity (135°C) <5 mPa·s, distillation yields of 94.7 wt% at 350°C, and 99.4 wt% at 540°C. 55 kg of 200°C oil residue and 20°C catalytic diesel were pumped into the primary extraction tank at a mass ratio of 1:3. The mixture in the primary extraction tank was subjected to three extraction cycles, each lasting 35 minutes. After the extraction, solid-liquid separation was performed. The separated solid material was pumped into the secondary extraction tank at 170°C along with 40°C catalytic diesel, with a solid-to-catalytic diesel mass ratio of 1:2.4. The mixed material in the secondary extraction tank was subjected to three cycles of extraction, each extraction time being 25 minutes. After the extraction, solid-liquid separation was performed, and the liquid material after desolidification was collected (including each stage, the same below). The extracted oil yield was 83.2%, and the metal ion content in the extracted oil was 43.9 mg / kg.

[0043] Example 2

[0044] The oil residue was desolidified using vacuum gas oil (VGO) as the solvent. VGO physical properties include 0.6 wt% carbon residue, 0.02 wt% ash, ≤8 mPa·s dynamic viscosity (135°C), and 98.9% distillation at 540°C. 45 kg of 280°C oil residue and 50°C vacuum gas oil were pumped into the primary extraction tank at a mass ratio of 1:5. The mixture in the primary extraction tank was subjected to three extraction cycles, each lasting 15 minutes. After extraction, solid-liquid separation was performed. The separated solid material was then mixed with 100°C VGO at 210°C and pumped into the secondary extraction tank at a mass ratio of 1:1. The mixture in the secondary extraction tank was subjected to three extraction cycles, each lasting 25 minutes. After extraction, solid-liquid separation was performed, and the desolidified liquid material (including each stage, the same applies below) was collected. The extracted oil yield was 81.8%, and the metal ion content in the extracted oil was 40.2 mg / kg.

[0045] Example 3

[0046] The oil residue was desolidified using paraxylene as solvent oil. 55 kg of 245°C oil residue and 35°C paraxylene were taken and pumped into the first extraction tank at a mass ratio of 1:4. The mixture in the first extraction tank was subjected to three cycles of extraction, with each extraction time of 35 minutes. After the extraction, solid-liquid separation was carried out, and the separated solid material was pumped into the second extraction tank at 195°C and 60°C xylene respectively. The mass ratio of the solid phase material to paraxylene was 1:3.6. The mixture in the second extraction tank was subjected to three cycles of extraction, with each extraction time of 25 minutes. After the extraction, solid-liquid separation was carried out, and the liquid material after desolidification was collected (including each stage, the same below). The extracted oil yield was 83.5%, and the metal ion content in the extracted oil was 38.4 mg / kg.

[0047] Example 4

[0048] The oil residue was desolidified using slurry bed diesel (firewood) as the solvent. The basic physical properties of the firewood were a carbon residue of 0.03 wt%, an ash content of 0.011 wt%, a dynamic viscosity (135°C) of <5 mPa·s, a distillate yield of 87.2 wt% at 350°C, and 99.4 wt% at 540°C. 45 kg of 180°C oil residue and 70°C firewood were pumped into the primary extraction tank at a mass ratio of 1:6. The mixture in the primary extraction tank was subjected to three extraction cycles, each lasting 15 minutes. After the extraction, solid-liquid separation was performed. The separated solid material was pumped into the secondary extraction tank at 195°C along with the 95°C firewood, with a solid-to-firewood mass ratio of 1:8. The mixed material in the secondary extraction tank was subjected to three cycles of extraction, each time for 25 minutes. After the extraction, solid-liquid separation was performed, and the liquid material after desolidification was collected (including each stage, the same below). The extracted oil yield was 82.6%, and the metal ion content in the extracted oil was 46.2 mg / kg.

[0049] Example 5

[0050] Coker gas oil (CGO) was used as the solvent oil to desolidify the oil residue. The VGO physical properties were 0.38 wt% residual carbon, 0.032 wt% ash, ≤8 mPa·s dynamic viscosity (135°C), and 98.4% distillate at 540°C. 55 kg of 300°C oil residue and 15°C CGO were pumped into the primary extraction tank at a mass ratio of 1:4. The mixture in the primary extraction tank was extracted three times, each extraction lasting 35 minutes. After the extraction, solid-liquid separation was performed. The separated solid material was pumped into the secondary extraction tank at 220°C and 30°C xylene at a mass ratio of 1:0.4. The mixed material in the secondary extraction tank was subjected to three cycles of extraction, each extraction time was 25 minutes, and solid-liquid separation was performed after the extraction. The liquid material after desolidification was collected (including each stage, the same below). The extracted oil yield was 81.8%, and the metal ion content in the extracted oil was 43.5 mg / kg.

[0051] Example 6

[0052] The oil residue was desolidified using mixed aromatics (isopropylbenzene:m-xylene (mass ratio) = 1:4) as the solvent. 55 kg of 205°C oil residue and 25°C mixed aromatics were pumped into the first extraction tank at a mass ratio of 1:2. The mixture in the first extraction tank was subjected to three cycles of extraction, each lasting 35 minutes. After the extraction, solid-liquid separation was performed. The separated solid material was pumped into the second extraction tank at 180°C and 30°C catalytic fuel, with a mass ratio of 1:2. The mixture in the second extraction tank was subjected to three cycles of extraction, each lasting 25 minutes. After the extraction, solid-liquid separation was performed, and the desolidified liquid material was collected (including each stage, the same applies below). The extracted oil yield was 83.5%, and the metal ion content in the extracted oil was 39.8 mg / kg.

[0053] Example 7 (Examples 7-9, first level, non-preferred mode, corresponding to Examples 1-3, the effect is worse)

[0054] Diesel fuel (catalytic diesel) from the catalytic cracking unit was used as solvent oil to desolidify the oil residue. The basic physical properties of the catalytic diesel were: residual carbon 0.062 wt%, ash 0.017 wt%, dynamic viscosity (135°C) <5 mPa·s, distillation yields of 94.7 wt% at 350°C, and 99.4 wt% at 540°C. 55 kg of 200°C oil residue and 20°C catalytic diesel were pumped into the primary extraction tank at a mass ratio of 1:3. The mixture in the primary extraction tank was subjected to three extraction cycles, each lasting 35 minutes. After the extraction, solid-liquid separation was performed. The separated solid material was pumped into the secondary extraction tank at 200°C along with the 20°C catalytic diesel, with a mass ratio of 1:3 between the solid phase and the catalytic diesel. The mixed material in the secondary extraction tank was subjected to three cycles of extraction, each extraction time was 25 minutes, and solid-liquid separation was performed after the extraction. The liquid material after desolidification was collected (including each stage, the same below). The extracted oil yield was 75.2%, and the metal ion content in the extracted oil was 62.3 mg / kg.

[0055] Example 8

[0056] The oil residue was desolidified using vacuum gas oil (VGO) as the solvent. VGO physical properties include 0.6 wt% carbon residue, 0.02 wt% ash, ≤8 mPa·s dynamic viscosity (135°C), and 98.9% distillation at 540°C. 45 kg of 170°C oil residue and 80°C vacuum gas oil were pumped into the primary extraction tank at a mass ratio of 1:5. The mixture in the primary extraction tank was subjected to three extraction cycles, each lasting 15 minutes. After extraction, solid-liquid separation was performed. The separated solid material was then pumped into the secondary extraction tank at 170°C and VGO at 80°C, with a mass ratio of 1:6. The mixture in the secondary extraction tank was subjected to three extraction cycles, each lasting 25 minutes. After extraction, solid-liquid separation was performed, and the desolidified liquid material (including each stage, the same applies below) was collected. The extracted oil yield was 73.5%, and the metal ion content in the extracted oil was 66.4 mg / kg.

[0057] Example 9

[0058] The oil residue was desolidified using paraxylene as solvent oil. 55 kg of 165°C oil residue and 85°C paraxylene were taken and pumped into the first extraction tank at a mass ratio of 1:8. The mixture in the first extraction tank was extracted three times in a cycle, with each extraction time of 35 minutes. After the extraction, solid-liquid separation was carried out, and the separated solid material was pumped into the second extraction tank at 195°C and 80°C xylene respectively, with the mass ratio of solid phase material to paraxylene being 1:2. The mixture in the second extraction tank was extracted three times in a cycle, with each extraction time of 25 minutes. After the extraction, solid-liquid separation was carried out, and the liquid material after desolidification was collected (including each stage, the same below). The extracted oil yield was 73.7%, and the metal ion content in the extracted oil was 58.5 mg / kg.

[0059] Example 10

[0060] The oil residue was desolidified using diesel produced by a catalytic cracking unit (catalytic diesel) as solvent. The basic physical properties of the catalytic diesel were: residual carbon 0.062 wt%, ash 0.017 wt%, dynamic viscosity (135°C) <5 mPa·s, distillation yields of 94.7 wt% at 350°C, and 99.4 wt% at 540°C. 55 kg of 200°C oil residue and 20°C catalytic diesel were pumped into the primary extraction tank at a mass ratio of 1:3. The mixture in the primary extraction tank was subjected to three extraction cycles, each lasting 35 minutes. After the extraction, solid-liquid separation was performed. The separated solids were then pumped into the secondary extraction tank at 170°C along with 40°C para-xylene, with a mass ratio of 1:2.4 between the solids and para-xylene. The mixed material in the secondary extraction tank was subjected to three cycles of extraction, each time for 25 minutes. After the extraction, solid-liquid separation was performed, and the liquid material after desolidification was collected (including each stage, the same below). The extracted oil yield was 88.5%, and the metal ion content in the extracted oil was 27.2 mg / kg.

[0061] Example 11

[0062] The oil residue was desolidified using vacuum gas oil (VGO) as the solvent. VGO physical properties include 0.6wt% carbon residue, 0.02wt% ash, ≤8mPa·s dynamic viscosity (135°C), and 98.9% distillate at 540°C. 45kg of 280°C oil residue and 50°C vacuum gas oil were pumped into the primary extraction tank at a mass ratio of 1:5. The mixture in the primary extraction tank was subjected to three extraction cycles, each lasting 15 minutes. After the extraction, solid-liquid separation was performed. The separated solid material was pumped into the secondary extraction tank at 210°C along with 100°C cumene, with a mass ratio of 1:1 between the solid phase and cumene. The mixed material in the secondary extraction tank was subjected to three cycles of extraction, each extraction time being 25 minutes. After the extraction, solid-liquid separation was performed, and the liquid material after desolidification was collected (including each stage, the same below). The extracted oil yield was 89.2%, and the metal ion content in the extracted oil was 25.3 mg / kg.

[0063] Example 12

[0064] The oil residue was desolidified using paraxylene as solvent oil. 55 kg of 245°C oil residue and 35°C paraxylene were taken and pumped into the first extraction tank at a mass ratio of 1:4. The mixture in the first extraction tank was subjected to three cycles of extraction, with each extraction time of 35 minutes. After the extraction, solid-liquid separation was carried out, and the separated solid material was pumped into the second extraction tank at 195°C and 60°C para-diethylbenzene, respectively. The mass ratio of the solid phase material to para-diethylbenzene was 1:3.6. The mixture in the second extraction tank was subjected to three cycles of extraction, with each extraction time of 25 minutes. After the extraction, solid-liquid separation was carried out, and the liquid material after desolidification was collected (including each stage, the same below). The extracted oil yield was 91.9%, and the metal ion content in the extracted oil was 20.5 mg / kg.

[0065] Comparative Example 1 (Comparative Examples 1-3, the effect is worse than that of Examples 7-9)

[0066] Diesel fuel (catalytic diesel) from a catalytic cracking unit was used as solvent oil to desolidify the oil residue. The basic physical properties of the desolidified diesel were: residual carbon 0.062 wt%, ash 0.017 wt%, dynamic viscosity (135°C) <5 mPa·s, distillation yields of 94.7 wt% at 350°C, and 99.4 wt% at 540°C. 55 kg of 200°C oil residue and 20°C desolidified diesel were pumped into the primary extraction tank at a mass ratio of 1:6. The mixture in the primary extraction tank was subjected to six extraction cycles, with the first three extractions lasting 35 minutes each, and the last three extractions lasting 25 minutes each. After the extractions, solid-liquid separation was performed, and the desolidified liquid was collected. The extracted oil yield was 56.5%, and the metal ion content in the extracted oil was 178.6 mg / kg.

[0067] Comparative Example 2

[0068] The oil residue was desolidified using vacuum gas oil (VGO) as the solvent. VGO physical properties include 0.6wt% residual carbon, 0.02wt% ash, ≤8mPa·s dynamic viscosity (135°C), and 98.9% distillate at 540°C. 45kg of 170°C oil residue and 80°C vacuum gas oil were pumped into the primary extraction tank at a mass ratio of 1:11. The mixture in the primary extraction tank was subjected to six extraction cycles, with the first three extractions lasting 15 minutes each, and the last three extractions lasting 25 minutes each. After the extractions, solid-liquid separation was performed, and the desolidified liquid material was collected. The extracted oil yield was 57.2%, and the metal ion content in the extracted oil was 166.5mg / kg.

[0069] Comparative Example 3

[0070] The oil residue was desolidified using paraxylene as the solvent. 55 kg of 165°C oil residue and 85°C paraxylene were pumped into the primary extraction tank at a mass ratio of 1:10. The mixture in the primary extraction tank was subjected to six cycles of extraction, with each extraction lasting 35 minutes for the first three extractions and 25 minutes for the subsequent three extractions. After the extractions, solid-liquid separation was performed, and the desolidified liquid material was collected. The extracted oil yield was 55.2%, and the metal ion content in the extracted oil was 159.8 mg / kg.

Claims

1. A method for desolidifying oil residue from slurry bed hydrocracking, characterized by: The method comprises the following contents: slurry bed hydrocracking oil residue is subjected to N-stage extraction, where N is an integer greater than 2; the solid phase material obtained after separation of the material after the previous stage of extraction is subjected to the next stage of extraction; the material after the N-stage extraction is subjected to solid-liquid separation and then subjected to subsequent treatment respectively.

2. The method according to claim 1, wherein: The feed temperatures of the extracted materials in two adjacent stages are the same or different.

3. The method according to claim 2, wherein: The feed temperatures of the extracted materials in two adjacent stages are different, and it is further preferred that the feed temperatures show a decreasing trend.

4. The method according to claim 3, wherein: The feed temperature difference between the two adjacent stages of extracted materials is 25-80°C, preferably 30-70°C.

5. The method according to claim 1, wherein: The feed temperature of the solvents in the two adjacent extraction stages tends to increase.

6. The method according to claim 5, characterized in that: The difference in feed temperature of the adjacent two-stage extraction solvent is 20-60°C, preferably 25-50°C.

7. The method according to claim 1, wherein: The pumping temperature of the first-stage extraction slurry bed hydrocracking oil residue is 180-300°C, preferably 200-280°C, and the pumping temperature of the extraction solvent oil is 15-70°C, preferably 20-50°C.

8. The method according to claim 1, wherein: The mass ratio of the extracted material to the extraction solvent in any two adjacent stages is the same or different.

9. The method according to claim 8, characterized in that: It is preferred that the mass ratio of the extracted material to the extraction solvent in two adjacent stages shows a decreasing trend.

10. The method according to claim 1, wherein: The mass ratio of the first-stage extraction slurry bed hydrocracking oil residue to the extraction solvent is 1:2 to 1:6, preferably 1:3 to 1:

5.

11. The method according to claim 9, wherein: The mass ratio of the extracted materials to the extraction solvent in two adjacent stages is reduced by 10% to 90%, preferably by 20% to 80%.

12. The method according to claim 1, wherein: The slurry bed hydrocracking oil residue has the following properties: residual carbon ≥ 36wt%, ash ≥ 0.6wt%, dynamic viscosity (135℃) ≥ 50mPa·s, dynamic viscosity (250℃) ≥ 10mPa·s, distillation volume at 350℃ ≤ 2wt%, distillation volume at 540℃ ≤ 55wt%, and metal content of 3500-4500mg·kg -1 , preferably 3750~4250mg·kg -1 .

13. The method according to claim 1, wherein: The extraction solvent is aromatic hydrocarbon, diesel oil or wax oil; when the solvent is aromatic hydrocarbon, it is at least one of benzene, biphenyl, naphthalene, anthracene, toluene, p-xylene, o-xylene, m-xylene, diphenylmethane, triphenylmethane, p-diethylbenzene, m-diethylbenzene, n-propylbenzene, isopropylbenzene, butylbenzene, isobutylbenzene, pentylbenzene, dodecylbenzene and hexadecylbenzene; when the solvent is diesel oil, it is crude diesel oil obtained by crude oil fractionation, hydrocracking and catalytic cracking, and has the following properties: residual carbon ≤ 0.1 wt%, ash content ≤0.05wt%, dynamic viscosity (135℃) ≤8mPa·s, distillate at 350℃ ≥85wt%, distillate at 540℃ ≥98wt%; when the solvent oil is wax oil, it is atmospheric wax oil or coker wax oil, and the atmospheric wax oil and coker wax oil have the following properties: residual carbon ≤1.0wt%, ash content ≤0.08wt%, dynamic viscosity (135℃) ≤8mPa·s, distillate at 540℃ ≥98wt%.

14. The method according to claim 1, wherein: The first stage extraction solvent is diesel and / or wax oil.

15. The method according to claim 1, wherein: The slurry bed hydrocracking oil residue undergoes two-stage extraction, the first-stage extraction solvent is diesel and / or wax oil, and the second-stage extraction solvent is aromatic hydrocarbons.

16. The method according to claim 1, wherein: The number of cyclic extractions in any one stage of extraction is 1 to 6 times, preferably 2 to 4 times; the time for each cyclic extraction is 10 to 60 minutes, preferably 20 to 40 minutes.

17. The method according to claim 1, wherein: The solid phase material is further processed or directly coked or compounded with slurry bed hydrocracking oil residue for gasification and hydrogen production; the liquid phase material is used for subsequent processing and refining.

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